Studio
We publish the APKs.
Bobbis Systems makes Android apps and puts the install files on this site. Each app has its own page, with the APK, privacy, and terms.
These are sideload apps. You download the file and install it on the phone. There is no store account, and the apps here do not ask you to create one.
Calculator is shipping. The next app is VPN-Gateway: a phone app to manage a VPN gateway. The first box is a Raspberry Pi 3B+. Other hardware can follow.